1. Field of the Invention
This invention relates in general to certain new and useful improvements in improved gate-opening and closing apparatus and, more particularly, to gate-opening and closing apparatus and the method therefor which shifts a gate between an open and a closed position and which permits authorized manual activation thereof in the event of a failure of powered operation thereof.
2. Brief Description of the Prior Art
In recent years, there have been a number of gate opening and closing assemblies and particularly, automatic type opening and closing assemblies. These gate assemblies have received increasing prominence in many commercial applications. There are several types of gates which are moved from a closed position to an open position in order to provide access and back to a closed position in order to provide a type of security. One type of gate is a gate which is slidable on a trackway, or other mechanism, for movement in a linear direction. This type of gate shifts from an open position in a linear path to a closed position in order to block the access opening. Other types of gates have one vertical side portion thereof hingedly mounted so that the other vertical side portion is swingable away from a stationary structure to an open position and back toward the stationary structure to a closed position.
As indicated previously, the automatic gate openers, in particular, have received increased prominence in recent years. These automatic gate openers may operate on the basis of a remote control mechanism such that a party desiring to open or close the gate does not have to physically engage the gate. For example, the gate opening and closing apparatus may use a radio transmitter and receiver system, such that a radio transmitter, when actuated, will generate a particular frequency signal which is sensed by the receiver to automatically operate the gate or door in order to open the same or close the same.
These radio transmitter and receiver systems have been used with various types of gates. Moreover, they have also been used with gates having one vertical side wall hingedly mounted and the other vertical side wall of which moves with respect to the stationary structure.
Notwithstanding, various forms of gate operating mechanisms, as for example, simple electrical switches, are used in order to shift gates from the closed to the opened positions and from the opened to the closed positions with respect to an access opening.
In the case of the so-called "swing gates", that is gates which are hingedly mounted on one vertical margin, there has not been any effective mechanism for efficiently shifting the gate, particularly when the gate had a large overall length resulting from a rather large swing movement. One of the principal problems encountered with these types of gates is that the gate must be locked when it reaches the closed position. The lever arms or other drive mechanisms, which were used to shift the gate between the closed and open positions, could preferably be designed to provide some type of locking action. Notwithstanding, there were many occasions in which the gate could be forced open against the action of the gate opening and closing assembly by causing one or more components in the drive section to slip.
In swing gate opening and closing assemblies, there was not any effective means for overriding the mechanism itself in the event of a temporary emergency condition such as a power failure. In the case of an electrical power failure, the motor could not be operated to open and close the gate. Consequently, there needed to be an effective override means which permitted the gate to be opened or closed by manual operation, but which did not compromise the integrity of the mechanism when the power was available.